Investigators plan to beginning their study at April in 2016 and end at March in 2018.One hundred patients with renal calculi measuring smaller than 25 mm will be enrolled in this study. By simple random sampling technique, patients will be assigned to two 50-patient groups(group 1:F14,group2 :F12).All the patients will be diagnosed definitely before operations with non-contrast CT. Patients with positive preoperative urine culture should be treated with suitable antibiotics based on the culture sensitivity result for at least 72h before SMP. Patients who have negative urine culture should receive a single dose of broad spectrum antibiotic prophylaxis just prior to the procedure.